The purpose of this project is first, to develop and animal model (rat) in which trophoblastic neoplasia can be studied and second, to study biochemial changes in the trophoblast and adjacent uterine tissue during induction and growth of the tumor. Trophoblastic neoplasia is induced with DMBA in fetectomized 12-day pregnant rats. The presence of the tumors will be detected by assaying blood levels of rat chorionic mammotropin (RCM). Subsequently, growth characteristics will be related quantitatively to levels of RCM and key glycolytic, tricarboxylic acid cycle and pentose phosphate enzyme activities will be determined. The effects of varying levels and ratios of sex steroids, synthetic sex steroids and chemotherapeutic agents on RCM levels and biochemical parameters will also be determined. The major thrust of this project is to study these parameters in vivo, in relation to the animal model and subsequently, to utilize cell culture and other in vitro techniques as they may apply.